Vintage Outboard Carburetor Basic Maintenance for Johnson / Evinrude / OMC

Your vintage outboard motor can run for decades with easy to learn maintenance practices. This video provides a basic overview of a vintage carburetor off of a 1956 12HP Johnson / Evinrude / OMC engine. This carburetor design was re-used over a period of many years with minor differences from year to year.

Step 1: remove choke knob and mixture knobs.
Step 2: remove motor cover
Step 3: disconnect throttle linkage from carburetor (tiny cotter pin or bent wire)
Step 4: remove 2 nuts (7/16") holding carburetor onto intake manifold
Step 5: carburetor can be completely separated from engine
Step 6: turn carburetor upside down and remove 4 or 5 screws with a screwdriver
Step 7: remove float hinge pin by pushing one side of it with a small pointed tool
Step 8: remove float and needle valve
Step 9: remove gasket
Step 10: remove low speed mixture screw, packing nut and washers (the washers are probably inside the hole!)
Step 11: remove high speed mixture screw, packing nut and washers
Step 12: remove high speed carburetor jet with screw driver
Step 13: clean all parts and replace gaskets, float, needle valve as needed
Step 14: reassemble in reverse order
Step 15: before attempting to start the engine, pre-set the high speed and low speed mixture screw needle valves as follows:
High speed screw: A beginning "rough" adjustment for the
high-speed needle valve is 3/4 of a turn out
(counterclockwise) from the lightly seated
(closed) position.
Low speed screw: A beginning "rough" adjustment for the low-speed needle valve is from 1 to 1+1/2 of a turn out (counterclockwise from the lightly seated (closed) position.

Carburetor Tuning will be covered in a different session.